Financial Instruments Contractual Maturities of Types of Securities (Details) (USD $) In Millions, unless otherwise specified	Jul. 31, 2014
Cost
Due in 1 year	$ 540.3
Due in 1 year through 5 years	278.0
Total	818.3
Fair Value
Due in 1 year	540.4
Due in 1 year through 5 years	276.3
Total	$ 816.7

Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at fair value maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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